From Yu Kuai (with minor changes by Song Liu):
The background is that currently bitmap is using a global spin_lock,
causing lock contention and huge IO performance degradation for all raid
levels.
However, it's impossible to implement a new lock free bitmap with
current situation that md-bitmap exposes the internal implementation
with lots of exported apis. Hence bitmap_operations is invented, to
describe bitmap core implementation, and a new bitmap can be introduced
with a new bitmap_operations, we only need to switch to the new one
during initialization.
And with this we can build bitmap as kernel module, but that's not
our concern for now.
This version was tested with mdadm tests and lvm2 tests. This set does
not introduce new errors in these tests.
* md-6.12-bitmap: (42 commits)
md/md-bitmap: make in memory structure internal
md/md-bitmap: merge md_bitmap_enabled() into bitmap_operations
md/md-bitmap: merge md_bitmap_wait_behind_writes() into bitmap_operations
md/md-bitmap: merge md_bitmap_free() into bitmap_operations
md/md-bitmap: merge md_bitmap_set_pages() into struct bitmap_operations
md/md-bitmap: merge md_bitmap_copy_from_slot() into struct bitmap_operation.
md/md-bitmap: merge get_bitmap_from_slot() into bitmap_operations
md/md-bitmap: merge md_bitmap_resize() into bitmap_operations
md/md-bitmap: pass in mddev directly for md_bitmap_resize()
md/md-bitmap: merge md_bitmap_daemon_work() into bitmap_operations
md/md-bitmap: merge bitmap_unplug() into bitmap_operations
md/md-bitmap: merge md_bitmap_unplug_async() into md_bitmap_unplug()
md/md-bitmap: merge md_bitmap_sync_with_cluster() into bitmap_operations
md/md-bitmap: merge md_bitmap_cond_end_sync() into bitmap_operations
md/md-bitmap: merge md_bitmap_close_sync() into bitmap_operations
md/md-bitmap: merge md_bitmap_end_sync() into bitmap_operations
md/md-bitmap: remove the parameter 'aborted' for md_bitmap_end_sync()
md/md-bitmap: merge md_bitmap_start_sync() into bitmap_operations
md/md-bitmap: merge md_bitmap_endwrite() into bitmap_operations
md/md-bitmap: merge md_bitmap_startwrite() into bitmap_operations
...
Signed-off-by: Song Liu <song@kernel.org>
For flush request, md has a special flush handling to merge concurrent
flush request into single one, however, the whole mechanism is based on
a disk level spin_lock 'mddev->lock'. And fsync can be called quite
often in some user cases, for consequence, spin lock from IO fast path can
cause performance degradation.
Fortunately, the block layer already has flush handling to merge
concurrent flush request, and it only acquires hctx level spin lock. (see
details in blk-flush.c)
This patch removes the flush handling in md, and converts to use general
block layer flush handling in underlying disks.
Flush test for 4 nvme raid10:
start 128 threads to do fsync 100000 times, on arm64, see how long it
takes.
Test script:
void* thread_func(void* arg) {
int fd = *(int*)arg;
for (int i = 0; i < FSYNC_COUNT; i++) {
fsync(fd);
}
return NULL;
}
int main() {
int fd = open("/dev/md0", O_RDWR);
if (fd < 0) {
perror("open");
exit(1);
}
pthread_t threads[THREADS];
struct timeval start, end;
gettimeofday(&start, NULL);
for (int i = 0; i < THREADS; i++) {
pthread_create(&threads[i], NULL, thread_func, &fd);
}
for (int i = 0; i < THREADS; i++) {
pthread_join(threads[i], NULL);
}
gettimeofday(&end, NULL);
close(fd);
long long elapsed = (end.tv_sec - start.tv_sec) * 1000000LL + (end.tv_usec - start.tv_usec);
printf("Elapsed time: %lld microseconds\n", elapsed);
return 0;
}
Test result: about 10 times faster:
Before this patch: 50943374 microseconds
After this patch: 5096347 microseconds
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240827110616.3860190-1-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
Now that struct bitmap_page and bitmap is not used externally anymore,
move them from md-bitmap.h to md-bitmap.c (expect that dm-raid is still
using define marco 'COUNTER_MAX').
Also fix some checkpatch warnings.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240826074452.1490072-43-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
The structure is empty for now, and will be used in later patches to
merge in bitmap operations, so that bitmap implementation won't be
exposed.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240826074452.1490072-12-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
'struct md_cluster_operations' is not modified in this driver.
Constifying this structure moves some data to a read-only section, so
increase overall security.
On a x86_64, with allmodconfig, as an example:
Before:
======
text data bss dec hex filename
51941 1442 80 53463 d0d7 drivers/md/md-cluster.o
After:
=====
text data bss dec hex filename
52133 1246 80 53459 d0d3 drivers/md/md-cluster.o
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/3727f3ce9693cae4e62ae6778ea13971df805479.1719173852.git.christophe.jaillet@wanadoo.fr
The md driver wants to enforce a number of flags for all devices, even
when not inheriting them from the underlying devices. To make sure these
flags survive the queue_limits_set calls that md uses to update the
queue limits without deriving them form the previous limits add a new
md_init_stacking_limits helper that calls blk_set_stacking_limits and sets
these flags.
Fixes: 1122c0c1cc ("block: move cache control settings out of queue->flags")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240626142637.300624-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull in block limits branch, which exists as a shared branch for both
the block and SCSI tree.
* for-6.11/block-limits: (26 commits)
block: move integrity information into queue_limits
block: invert the BLK_INTEGRITY_{GENERATE,VERIFY} flags
block: bypass the STABLE_WRITES flag for protection information
block: don't require stable pages for non-PI metadata
block: use kstrtoul in flag_store
block: factor out flag_{store,show} helper for integrity
block: remove the blk_flush_integrity call in blk_integrity_unregister
block: remove the blk_integrity_profile structure
dm-integrity: use the nop integrity profile
md/raid1: don't free conf on raid0_run failure
md/raid0: don't free conf on raid0_run failure
block: initialize integrity buffer to zero before writing it to media
block: add special APIs for run-time disabling of discard and friends
block: remove unused queue limits API
sr: convert to the atomic queue limits API
sd: convert to the atomic queue limits API
sd: cleanup zoned queue limits initialization
sd: factor out a sd_discard_mode helper
sd: simplify the disable case in sd_config_discard
sd: add a sd_disable_write_same helper
...
Move the integrity information into the queue limits so that it can be
set atomically with other queue limits, and that the sysfs changes to
the read_verify and write_generate flags are properly synchronized.
This also allows to provide a more useful helper to stack the integrity
fields, although it still is separate from the main stacking function
as not all stackable devices want to inherit the integrity settings.
Even with that it greatly simplifies the code in md and dm.
Note that the integrity field is moved as-is into the queue limits.
While there are good arguments for removing the separate blk_integrity
structure, this would cause a lot of churn and might better be done at a
later time if desired. However the integrity field in the queue_limits
structure is now unconditional so that various ifdefs can be avoided or
replaced with IS_ENABLED(). Given that tiny size of it that seems like
a worthwhile trade off.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240613084839.1044015-13-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For different sync_action, sync_thread will use different max_sectors,
see details in md_sync_max_sectors(), currently both md_do_sync() and
pers->sync_request() in eatch iteration have to get the same
max_sectors. Hence pass in max_sectors for pers->sync_request() to
prevent redundant code.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240611132251.1967786-12-yukuai1@huaweicloud.com
The only difference is that "none" is removed and initial
last_sync_action will be idle.
On the one hand, this value is introduced by commit c4a3955145
("MD: Remember the last sync operation that was performed"), and the
usage described in commit message is not affected. On the other hand,
last_sync_action is not used in mdadm or mdmon, and none of the tests
that I can find.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240611132251.1967786-10-yukuai1@huaweicloud.com
Make code cleaner. and also use the action_name directly in kernel log:
- "check" instead of "data-check"
- "repair" instead of "requested-resync"
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240611132251.1967786-9-yukuai1@huaweicloud.com
MD_RECOVERY_RUNNING will always be set when trying to register a new
sync_thread, however, if md_start_sync() turns out to do nothing,
MD_RECOVERY_RUNNING will be cleared in this case. And during the race
window, action_store() will return -EBUSY, which will cause some
mdadm tests to fail. For example:
The test 07reshape5intr will add a new disk to array, then start
reshape:
mdadm /dev/md0 --add /dev/xxx
mdadm --grow /dev/md0 -n 3
And add_bound_rdev() from mdadm --add will set MD_RECOVERY_NEEDED,
then during the race windown, mdadm --grow will fail.
Fix the problem by waiting in action_store() during the race window,
fail only if sync_thread is registered.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240611132251.1967786-8-yukuai1@huaweicloud.com
In order to make code related to sync_thread cleaner in following
patches, also add detail comment about each sync action. And also
prepare to remove the related recovery_flags in the fulture.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240611132251.1967786-3-yukuai1@huaweicloud.com
Currently there are lots of flags with the same confusing prefix
"MD_REOCVERY_", and there are two main types of flags, sync thread runnng
status, I prefer prefix "SYNC_THREAD_", and sync thread action, I perfer
prefix "SYNC_ACTION_".
For now, rearrange and update comment to improve code readability,
there are no functional changes.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240611132251.1967786-2-yukuai1@huaweicloud.com
Commit cc27b0c78c ("md: fix deadlock between mddev_suspend() and
md_write_start()") aborted md_write_start() with false when mddev is
suspended, which fixed a deadlock if calling mddev_suspend() with
holding reconfig_mutex(). Since mddev_suspend() now includes
lockdep_assert_not_held(), it no longer holds the reconfig_mutex. This
makes previous abort unnecessary. Now, remove unnecessary abort and
change function return value to void.
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240525185257.3896201-2-linan666@huaweicloud.com
This reverts commit 3f9f231236.
Using 64bit for 'sync_io' is unnecessary from the gendisk side. This
overflow will not cause any functional impact, except for a UBSAN
warning. Solving this overflow requires introducing additional
calculations and checks which are not necessary. So just keep using
32bit for 'sync_io'.
Signed-off-by: Li Nan <linan122@huawei.com>
Link: https://lore.kernel.org/r/20240507023103.781816-1-linan666@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If iostats is disabled, disk_stats will not be updated and
part_stat_read_accum() only returns a constant value. In this case,
continuing to count sync_io and to check is_mddev_idle() is no longer
meaningful.
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240117031946.2324519-3-linan666@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
UBSAN reports this problem:
UBSAN: Undefined behaviour in drivers/md/md.c:8175:15
signed integer overflow:
-2147483291 - 2072033152 cannot be represented in type 'int'
Call trace:
dump_backtrace+0x0/0x310
show_stack+0x28/0x38
dump_stack+0xec/0x15c
ubsan_epilogue+0x18/0x84
handle_overflow+0x14c/0x19c
__ubsan_handle_sub_overflow+0x34/0x44
is_mddev_idle+0x338/0x3d8
md_do_sync+0x1bb8/0x1cf8
md_thread+0x220/0x288
kthread+0x1d8/0x1e0
ret_from_fork+0x10/0x18
'curr_events' will overflow when stat accum or 'sync_io' is greater than
INT_MAX.
Fix it by changing sync_io, last_events and curr_events to 64bit.
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240117031946.2324519-2-linan666@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
Just use the request_queue from the gendisk pointer in the relatively
few places that sill need it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed--by: Song Liu <song@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240303140150.5435-11-hch@lst.de
Add a few helpers that wrap the block queue limits API for use in MD.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed--by: Song Liu <song@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240303140150.5435-5-hch@lst.de
Add a helper to check for a DM-mapped MD device instead of using
the obfuscated ->gendisk or ->queue NULL checks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed--by: Song Liu <song@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240303140150.5435-4-hch@lst.de
Add a small wrapper around blk_add_trace_msg that hides some argument
dereferences and the check for a DM-mapped MD device.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed--by: Song Liu <song@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240303140150.5435-3-hch@lst.de
Add a helper to trace bio remapping that hides some argument
dereferences and the check for a DM-mapped MD device.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed--by: Song Liu <song@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240303140150.5435-2-hch@lst.de
For raid456, if reshape is still in progress, then IO across reshape
position will wait for reshape to make progress. However, for dm-raid,
in following cases reshape will never make progress hence IO will hang:
1) the array is read-only;
2) MD_RECOVERY_WAIT is set;
3) MD_RECOVERY_FROZEN is set;
After commit c467e97f07 ("md/raid6: use valid sector values to determine
if an I/O should wait on the reshape") fix the problem that IO across
reshape position doesn't wait for reshape, the dm-raid test
shell/lvconvert-raid-reshape.sh start to hang:
[root@fedora ~]# cat /proc/979/stack
[<0>] wait_woken+0x7d/0x90
[<0>] raid5_make_request+0x929/0x1d70 [raid456]
[<0>] md_handle_request+0xc2/0x3b0 [md_mod]
[<0>] raid_map+0x2c/0x50 [dm_raid]
[<0>] __map_bio+0x251/0x380 [dm_mod]
[<0>] dm_submit_bio+0x1f0/0x760 [dm_mod]
[<0>] __submit_bio+0xc2/0x1c0
[<0>] submit_bio_noacct_nocheck+0x17f/0x450
[<0>] submit_bio_noacct+0x2bc/0x780
[<0>] submit_bio+0x70/0xc0
[<0>] mpage_readahead+0x169/0x1f0
[<0>] blkdev_readahead+0x18/0x30
[<0>] read_pages+0x7c/0x3b0
[<0>] page_cache_ra_unbounded+0x1ab/0x280
[<0>] force_page_cache_ra+0x9e/0x130
[<0>] page_cache_sync_ra+0x3b/0x110
[<0>] filemap_get_pages+0x143/0xa30
[<0>] filemap_read+0xdc/0x4b0
[<0>] blkdev_read_iter+0x75/0x200
[<0>] vfs_read+0x272/0x460
[<0>] ksys_read+0x7a/0x170
[<0>] __x64_sys_read+0x1c/0x30
[<0>] do_syscall_64+0xc6/0x230
[<0>] entry_SYSCALL_64_after_hwframe+0x6c/0x74
This is because reshape can't make progress.
For md/raid, the problem doesn't exist because register new sync_thread
doesn't rely on the IO to be done any more:
1) If array is read-only, it can switch to read-write by ioctl/sysfs;
2) md/raid never set MD_RECOVERY_WAIT;
3) If MD_RECOVERY_FROZEN is set, mddev_suspend() doesn't hold
'reconfig_mutex', hence it can be cleared and reshape can continue by
sysfs api 'sync_action'.
However, I'm not sure yet how to avoid the problem in dm-raid yet. This
patch on the one hand make sure raid_message() can't change
sync_thread() through raid_message() after presuspend(), on the other
hand detect the above 3 cases before wait for IO do be done in
dm_suspend(), and let dm-raid requeue those IO.
Cc: stable@vger.kernel.org # v6.7+
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Xiao Ni <xni@redhat.com>
Acked-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240305072306.2562024-9-yukuai1@huaweicloud.com
Add new helpers:
void md_idle_sync_thread(struct mddev *mddev);
void md_frozen_sync_thread(struct mddev *mddev);
void md_unfrozen_sync_thread(struct mddev *mddev);
The helpers will be used in dm-raid in later patches to fix regressions
and prevent calling md_reap_sync_thread() directly.
Cc: stable@vger.kernel.org # v6.7+
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Xiao Ni <xni@redhat.com>
Acked-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240305072306.2562024-3-yukuai1@huaweicloud.com
For raid1, each read will iterate all the rdevs from conf and check if
any rdev is non-rotational, then choose rdev with minimal IO inflight
if so, or rdev with closest distance otherwise.
Disk nonrot info can be changed through sysfs entry:
/sys/block/[disk_name]/queue/rotational
However, consider that this should only be used for testing, and user
really shouldn't do this in real life. Record the number of non-rotational
disks in conf, to avoid checking each rdev in IO fast path and simplify
read_balance() a little bit.
Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240229095714.926789-4-yukuai1@huaweicloud.com
The current api is_badblock() must pass in 'first_bad' and
'bad_sectors', however, many caller just want to know if there are
badblocks or not, and these caller must define two local variable that
will never be used.
Add a new helper rdev_has_badblock() that will only return if there are
badblocks or not, remove unnecessary local variables and replace
is_badblock() with the new helper in many places.
There are no functional changes, and the new helper will also be used
later to refactor read_balance().
Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240229095714.926789-2-yukuai1@huaweicloud.com
rcu is not used correctly here, because synchronize_rcu() is called
before replacing old value, for example:
remove_and_add_spares // other path
synchronize_rcu
// called before replacing old value
set_bit(RemoveSynchronized)
rcu_read_lock()
rdev = conf->mirros[].rdev
pers->hot_remove_disk
conf->mirros[].rdev = NULL;
if (!test_bit(RemoveSynchronized))
synchronize_rcu
/*
* won't be called, and won't wait
* for concurrent readers to be done.
*/
// access rdev after remove_and_add_spares()
rcu_read_unlock()
Fortunately, there is a separate rcu protection to prevent such rdev
to be freed:
md_kick_rdev_from_array //other path
rcu_read_lock()
rdev = conf->mirros[].rdev
list_del_rcu(&rdev->same_set)
rcu_read_unlock()
/*
* rdev can be removed from conf, but
* rdev won't be freed.
*/
synchronize_rcu()
free rdev
Hence remove this useless flag and prepare to remove rcu protection to
access rdev from 'conf'.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20231125081604.3939938-2-yukuai1@huaweicloud.com
-----BEGIN PGP SIGNATURE-----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=sace
-----END PGP SIGNATURE-----
Merge tag 'for-6.7/block-2023-10-30' of git://git.kernel.dk/linux
Pull block updates from Jens Axboe:
- Improvements to the queue_rqs() support, and adding null_blk support
for that as well (Chengming)
- Series improving badblocks support (Coly)
- Key store support for sed-opal (Greg)
- IBM partition string handling improvements (Jan)
- Make number of ublk devices supported configurable (Mike)
- Cancelation improvements for ublk (Ming)
- MD pull requests via Song:
- Handle timeout in md-cluster, by Denis Plotnikov
- Cleanup pers->prepare_suspend, by Yu Kuai
- Rewrite mddev_suspend(), by Yu Kuai
- Simplify md_seq_ops, by Yu Kuai
- Reduce unnecessary locking array_state_store(), by Mariusz
Tkaczyk
- Make rdev add/remove independent from daemon thread, by Yu Kuai
- Refactor code around quiesce() and mddev_suspend(), by Yu Kuai
- NVMe pull request via Keith:
- nvme-auth updates (Mark)
- nvme-tcp tls (Hannes)
- nvme-fc annotaions (Kees)
- Misc cleanups and improvements (Jiapeng, Joel)
* tag 'for-6.7/block-2023-10-30' of git://git.kernel.dk/linux: (95 commits)
block: ublk_drv: Remove unused function
md: cleanup pers->prepare_suspend()
nvme-auth: allow mixing of secret and hash lengths
nvme-auth: use transformed key size to create resp
nvme-auth: alloc nvme_dhchap_key as single buffer
nvmet-tcp: use 'spin_lock_bh' for state_lock()
powerpc/pseries: PLPKS SED Opal keystore support
block: sed-opal: keystore access for SED Opal keys
block:sed-opal: SED Opal keystore
ublk: simplify aborting request
ublk: replace monitor with cancelable uring_cmd
ublk: quiesce request queue when aborting queue
ublk: rename mm_lock as lock
ublk: move ublk_cancel_dev() out of ub->mutex
ublk: make sure io cmd handled in submitter task context
ublk: don't get ublk device reference in ublk_abort_queue()
ublk: Make ublks_max configurable
ublk: Limit dev_id/ub_number values
md-cluster: check for timeout while a new disk adding
nvme: rework NVME_AUTH Kconfig selection
...
Convert md to use bdev_open_by_dev() and pass the handle around. We also
don't need the 'Holder' flag anymore so remove it.
CC: linux-raid@vger.kernel.org
CC: Song Liu <song@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230927093442.25915-11-jack@suse.cz
Signed-off-by: Christian Brauner <brauner@kernel.org>
pers->prepare_suspend() is not used anymore and can be removed.
Reverts following three commit:
- commit 431e61257d ("md: export md_is_rdwr() and is_md_suspended()")
- commit 3e00777d51 ("md: add a new api prepare_suspend() in
md_personality")
- commit 868bba54a3 ("md/raid5: fix a deadlock in the case that reshape
is interrupted")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20231016100240.540474-1-yukuai1@huaweicloud.com
Now that the old apis are removed, __mddev_suspend/resume() can be
renamed to their original names.
This is done by:
sed -i "s/__mddev_suspend/mddev_suspend/g" *.[ch]
sed -i "s/__mddev_resume/mddev_resume/g" *.[ch]
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20231010151958.145896-20-yukuai1@huaweicloud.com
Now that mddev_suspend() and mddev_resume() is not used anywhere, remove
them, and remove 'MD_ALLOW_SB_UPDATE' and 'MD_UPDATING_SB' as well.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20231010151958.145896-19-yukuai1@huaweicloud.com
Now that except for stopping the array, all the callers already suspend
the array, there is no need to suspend anymore, hence remove the second
parameter.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20231010151958.145896-15-yukuai1@huaweicloud.com
The new helpers suspend the array first and then lock the array,
Prepare to refactor from:
mddev_lock/lock_nointr
mddev_suspend
...
mddev_resuem
mddev_lock
With:
mddev_suspend_and_lock/lock_nointr
...
mddev_unlock_and_resume
After all the use cases is refactored, mddev_suspend/resume() will be
removed.
And mddev_suspend_and_lock() will also replace mddev_lock() for the case
that the array will be reconfigured, in order to synchronize with io to
prevent problems in many corner cases.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20231010151958.145896-6-yukuai1@huaweicloud.com
Advantages for new apis:
- reconfig_mutex is not required;
- the weird logical that suspend array hold 'reconfig_mutex' for
mddev_check_recovery() to update superblock is not needed;
- the specail handling, 'pers->prepare_suspend', for raid456 is not
needed;
- It's safe to be called at any time once mddev is allocated, and it's
designed to be used from slow path where array configuration is changed;
- the new helpers is designed to be called before mddev_lock(), hence
it support to be interrupted by user as well.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20231010151958.145896-5-yukuai1@huaweicloud.com
Currently 'writes_pending' is initialized in pers->run for raid1/5/10,
and it's freed while deleing mddev, instead of pers->free. pers->run can
be called multiple times before mddev is deleted, and a helper
mddev_init_writes_pending() is used to prevent 'writes_pending' to be
initialized multiple times, this usage is safe but a litter weird.
On the other hand, 'writes_pending' is only initialized for raid1/5/10,
however, it's used in common layer, for example:
array_state_store
set_in_sync
if (!mddev->in_sync) -> in_sync is used for all levels
// access writes_pending
There might be some implicit dependency that I don't recognized to make
sure 'writes_pending' can only be accessed for raid1/5/10, but there are
no comments about that.
By the way, it make sense to initialize 'writes_pending' in common layer
because there are already three levels use it.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230825030956.1527023-3-yukuai1@huaweicloud.com
'active_io' is used for mddev_suspend() and it's initialized in
md_run(), this restrict that 'reconfig_mutex' must be held and
"mddev->pers" must be set before calling mddev_suspend().
Initialize 'active_io' early so that mddev_suspend() is safe to call
once mddev is allocated, this will be helpful to refactor
mddev_suspend() in following patches.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230825030956.1527023-2-yukuai1@huaweicloud.com
It's a little weird to borrow 'del_work' for md_start_sync(), declare
a new work_struct 'sync_work' for md_start_sync().
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230825031622.1530464-2-yukuai1@huaweicloud.com
Commit a1d7671910 ("md: use mddev->external to select holder in
export_rdev()") fix the problem that 'claim_rdev' is used for
blkdev_get_by_dev() while 'rdev' is used for blkdev_put().
However, if mddev->external is changed from 0 to 1, then 'rdev' is used
for blkdev_get_by_dev() while 'claim_rdev' is used for blkdev_put(). And
this problem can be reporduced reliably by following:
New file: mdadm/tests/23rdev-lifetime
devname=${dev0##*/}
devt=`cat /sys/block/$devname/dev`
pid=""
runtime=2
clean_up_test() {
pill -9 $pid
echo clear > /sys/block/md0/md/array_state
}
trap 'clean_up_test' EXIT
add_by_sysfs() {
while true; do
echo $devt > /sys/block/md0/md/new_dev
done
}
remove_by_sysfs(){
while true; do
echo remove > /sys/block/md0/md/dev-${devname}/state
done
}
echo md0 > /sys/module/md_mod/parameters/new_array || die "create md0 failed"
add_by_sysfs &
pid="$pid $!"
remove_by_sysfs &
pid="$pid $!"
sleep $runtime
exit 0
Test cmd:
./test --save-logs --logdir=/tmp/ --keep-going --dev=loop --tests=23rdev-lifetime
Test result:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 960 at block/bdev.c:618 blkdev_put+0x27c/0x330
Modules linked in: multipath md_mod loop
CPU: 0 PID: 960 Comm: test Not tainted 6.5.0-rc2-00121-g01e55c376936-dirty #50
RIP: 0010:blkdev_put+0x27c/0x330
Call Trace:
<TASK>
export_rdev.isra.23+0x50/0xa0 [md_mod]
mddev_unlock+0x19d/0x300 [md_mod]
rdev_attr_store+0xec/0x190 [md_mod]
sysfs_kf_write+0x52/0x70
kernfs_fop_write_iter+0x19a/0x2a0
vfs_write+0x3b5/0x770
ksys_write+0x74/0x150
__x64_sys_write+0x22/0x30
do_syscall_64+0x40/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Fix the problem by recording if 'rdev' is used as holder.
Fixes: a1d7671910 ("md: use mddev->external to select holder in export_rdev()")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230825025532.1523008-3-yukuai1@huaweicloud.com
Commit ba9d9f1a707f ("Revert "md: unlock mddev before reap sync_thread in
action_store"") removed the scenario of calling md_unregister_thread()
without holding mddev->reconfig_mutex, so add a lock holding check before
acquiring mddev->sync_thread by passing mdev to md_unregister_thread().
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20230803071711.2546560-1-lilingfeng@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
Currently, 'active_io' is grabbed before make_reqeust() is called, and
it's dropped immediately make_reqeust() returns. Hence 'active_io'
actually means io is dispatching, not io is inflight.
For raid0 and raid456 that io accounting is enabled, 'active_io' will
also be grabbed when bio is cloned for io accounting, and this 'active_io'
is dropped until io is done.
Always clone new bio so that 'active_io' will mean that io is inflight,
raid1 and raid10 will switch to use this method in later patches.
Now that bio will be cloned even if io accounting is disabled, also
rename related structure from '*_acct_*' to '*_clone_*'.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230621165110.1498313-3-yukuai1@huaweicloud.com
'io_acct_set' is only used for raid0 and raid456, prepare to use it for
raid1 and raid10, so that io accounting from different levels can be
consistent.
By the way, follow up patches will also use this io clone mechanism to
make sure 'active_io' represents in flight io, not io that is dispatching,
so that mddev_suspend will wait for io to be done as designed.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230621165110.1498313-2-yukuai1@huaweicloud.com
Our test found a following deadlock in raid10:
1) Issue a normal write, and such write failed:
raid10_end_write_request
set_bit(R10BIO_WriteError, &r10_bio->state)
one_write_done
reschedule_retry
// later from md thread
raid10d
handle_write_completed
list_add(&r10_bio->retry_list, &conf->bio_end_io_list)
// later from md thread
raid10d
if (!test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags))
list_move(conf->bio_end_io_list.prev, &tmp)
r10_bio = list_first_entry(&tmp, struct r10bio, retry_list)
raid_end_bio_io(r10_bio)
Dependency chain 1: normal io is waiting for updating superblock
2) Trigger a recovery:
raid10_sync_request
raise_barrier
Dependency chain 2: sync thread is waiting for normal io
3) echo idle/frozen to sync_action:
action_store
mddev_lock
md_unregister_thread
kthread_stop
Dependency chain 3: drop 'reconfig_mutex' is waiting for sync thread
4) md thread can't update superblock:
raid10d
md_check_recovery
if (mddev_trylock(mddev))
md_update_sb
Dependency chain 4: update superblock is waiting for 'reconfig_mutex'
Hence cyclic dependency exist, in order to fix the problem, we must
break one of them. Dependency 1 and 2 can't be broken because they are
foundation design. Dependency 4 may be possible if it can be guaranteed
that no io can be inflight, however, this requires a new mechanism which
seems complex. Dependency 3 is a good choice, because idle/frozen only
requires sync thread to finish, which can be done asynchronously that is
already implemented, and 'reconfig_mutex' is not needed anymore.
This patch switch 'idle' and 'frozen' to wait sync thread to be done
asynchronously, and this patch also add a sequence counter to record how
many times sync thread is done, so that 'idle' won't keep waiting on new
started sync thread.
Noted that raid456 has similiar deadlock([1]), and it's verified[2] this
deadlock can be fixed by this patch as well.
[1] https://lore.kernel.org/linux-raid/5ed54ffc-ce82-bf66-4eff-390cb23bc1ac@molgen.mpg.de/T/#t
[2] https://lore.kernel.org/linux-raid/e9067438-d713-f5f3-0d3d-9e6b0e9efa0e@huaweicloud.com/
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230529132037.2124527-5-yukuai1@huaweicloud.com
